Air conditioning system



m 23, QQS., R Q P CRAWFORD AIR CONDITIONING SYSTEM Filed July 21, 1939 4 Sheets-Sheet 2 Rober BRCrdLworaL Nm 23, H943.

R. B. P. .CRAWFORD AIR CONDITIONING SYSTEM Filed July 21, 19:59

4 Sheets-Sheex"l 3 inuenior o-7. Rober BR Crawford NRW-1ER NW 23 WW R. B. P. CRAWFOR AIR CONDITIONING SYSTEM Filed July 21. 1939 4 Sheets-Sheet NM ZmJU MWJOOU www g Robert BI. Crawford horneg Patented Nov. 23, 1943 AIR CONDITIONING SYSTEM Robert B. P. Crawford, Miami, Fla.

Application July 21, 1939, Serial No. 285,736

12 Claims.

This invention relates to an air conditioning system and while it has been shown and described With particular reference to the conditioning of an egg incubator, it should be understood that many of the featuresthereof are of utility in the conditioningof structures in general.

In the hatching of eggs, the number of chicks that are hatched for a given number of fertile eggs depends upon the maintenance of proper conditions of' temperature and humidity during the various stages of incubation. Thus, during the early stages of incubation, it may be necessary to supply heat to the eggs to maintain them at the proper temperature of approximately 100 F. Duringthe latter stages of incubation, the eggs generate a large amount of heat and it may be necessary to cool these stages to maintain the temperature thereof at the proper value. In accordance with the teachings of my invention, the eggs are carried through the incubator by means of a belt which requires approximately twenty-one days for the eggs to move from one end of the incubator to the other. The incubator may be divided into several stages, as for example seven stages in each of which the eggs remain for three days. Suitable heat exchanger coils are provided in the walls of each stage, and through these coils water or other suitable heat exchanging :fluid is circulated, the water absorbing heat from the latter stages and giving this heat up to the earlier stages, the flow of Water through the various stages being controlled by means of thermostats located in each stage in the more specific embodiment of my invention.

Under many conditions it may be necessary to additionally heat or cool the water, and for this purpose a refrigeration system is provided, the evaporator thereof providing the necessary cooling and the condenser thereof providing the necessary heating. By reason of the fact that the heat generated in the latter stages is used to provide heat in the early stages, the necessary additional heating or cooling may be eected by the provision of a refrigeration system of relatively small capacity.

Another factor in increasing the yield of chicks from a given number of fertile eggs is in maintaining the air in the incubator in a condition of purity. This is generally done by circulating fresh air through the incubator, but previous practice has required the circulation of a large volume of air through the incubator, since the air also served to maintain'desired belt enters the incubator and eggs are delivered temperatures in various portions thereof. It has also been the practice to recirculate a large amount of the air to reduce the operating expense of the systems. The circulation `of the air has resultedin the spreading of germs from egg to egg. and chemicals used-to reduce the germ concentration of the air have resulted in the killing of a number of embryo chicks. In accordance with my invention, since most of the heating and cooling is effected lby the use of the coils aforementioned, the circulation of air to eifect the heating and cooling is unnecessary, and only suiiicient air need be circulated to maintain the humidity at the proper value and to maintain the air ina clean condition and to remove the excess CO2 and H2O vapor formed during the incubating process. The air is passed over the heat exchanger coils and upwardly through the conveyor belt and is exhausted through the upper portion of the casing. The conveyor belt is so constructed that the air passing over one egg is unable to contact anyA other egg, and thus the spreading of germs from egg to egg'is minimized.

Provision is also made for testing the eggs passing through the incubator and ejecting the sterile eggs before they have been in the in` cubator for too long a period of time so that the eggs may be used for a useful purpose, such 1 as the manufacture of egg powder. Provision is also made for cleaning and sterilizing the belt as it leaves the incubator, so that as the thereto, it will be free of dirt and germs.

In addition to the features enumerated above, means for accurately controlling the humidity in the incubator are employed. Also, the excess sensible and latent heat removed bythe air leaving the incubator may be imparted to the air entering the incubator, thus increasing the operating efiiciency of the system, and permitting fresh air only to enter the incubator, without increasing to any appreciable extent the operating expense thereof.

It is accordingly an object of my invention to provide an egg incubator embodying the various features outlined above and other novel features set forth in the accompanying specification and claims.

It is also an object of myinvention to provide av of a novel control arrangement for an air conditioning system.

V'Other objects and advantages will become apparent upon a study of the speciiicationand claims and the appended drawings, wherein like reference characters indicate like parts in the various views and wherein,

Figure 1 is a view with certain parts shown in cross section of one form of conditioning system embodying my invention,

Figure 2 is a wiring diagram of the control` system of Figure 1,

Figure 3 is a schematic view of the egg ejecting mechanism,

an egg incubator to which the conditioning system embodying my invention is to be applied. A

belt travelling over pulleys l2 and I3 carries Suitable guide the eggs through the incubator. pulleys i4 are located within the incubator to guide the belt therethrough and these pulleys are alternately arranged at diierent levels within the incubator for causing the belt to travel up and down on its course therethrough so thatthe eggs carried thereby may be turned at frequent intervals. The belt carries suitable spacing elements l5 so that each egg carried thereby is in a separate compartment on the belt and the belt is formed of suitable porous material to permit upward circulation of air through the belt and past the eggs carried thereby. Since the circulation of air is upward through the belt and incubator, the spacingelements carried by the belt and separating the various eggs prevent any portion of the airfrom contacting more than one egg so as to prevent or minimize the spreading of germs from one egg to another, and by reason of this and the accurate control of the temperature and humidity throughout the incubator, the mortality of the eggs is minimized. Suitable means to be later described in detail are provided for determining sterilization of eggs, and releasing sterile eggs from the belt, the eggs leaving the incubator by way of the runway i3 in a manner to be later set forth. f

The travel of the belt through the incubator is of such speed that it requires approximately twenty-onedays for an egg t0 travel from the entrance I6 of the incubator to the exit i7. 'I'he incubator for purposes of illustration is shown as being divided into seven stages 2B, 2|, 22, 23, 24, 25, and 26, in each of which stages the eggs remain for a period of approximately three days. Suitable means Well known in the art may be provided for loading the eggs on the belt I 5, and

removing the chicks from the belt as they leave the incubator. Suitable means 21 may also be provided for scrubbing and dlsinfecting the belt after it leaves the incubator, one preferred construction of such means being more fully disclosed hereinafter.

The interior walls of the incubating chamber, as illustrated by the reference characters 28 and 29, may be formed of suitable porous material which permits air to flow readily therethrough. The outer walls 3U ofthe incubator may be formed of any suitable heat insulating material and these walls are spaced from the inner walls by means of the passages 3| and 32. A fan 33 driven by a motor 34 causes air to flow by means of the passageway 3| through the lower wall 29 of the incubator and the air passes upwardly through the y second chamber 38 carrying suitable humiditying and dehumidifyingmeans to be later described, the heat exchanger 40 and the passageway 4| to the fan inlet. The air leaving the incubator by way of the passageway 32 passes downwardly through the chamber 4| past the heat exchanger 40 whereby the air passing. to the fan passes in heat exchange relationship with the air leaving the incubator by way of the chamber 20 and the exit 42.

Embedded within the porous walls 28 and 29 are the heating and cooling coils. During the early. stages of incubation, assuming the room wherein the incubator is located is at F., the eggs in stages 2li, 2 I, and 22 will need to be heated, neither heating .nor cooling may be required of the eggs in stage 23, but since the eggs generate va considerable amount of heat during the latter stages of incubation, cooling may be required ofl the eggs in stages 24, 25, and 26. Accordingly stages 20, 2| and 22 have their walls provided with heating coils 50, 5|, and 52, the stage 23 may have its walls provided with cooling coils 53 since at certain times this stage may require a certain amount of cooling and stages 24, "l2 5, and 26 have their walls provided with the cooling coils 54, 55,

" and 56. These various coils will be provided in the upper and lower walls of the chamber and may also be embedded in the side walls thereof and are provided to take care of the heat to maintain the eggs in the early stages of incubation up to the proper temperature and also take care of the cooling to keep the eggs in the latter stages down to the proper temperature and thus eliminate heating or cooling through the shell of the incubator or from the surroundings. 'I'he circulation of air through the incubator is not for the purpose of heating or cooling the eggs to any extent but is for the purpose of maintaining the air within the incubator in a state of purity and at the proper relative humidity. i

Water is supplied to the various coils 5|) to 56 under ythe control of suitable valves and pumps to ybe hereinafter described, the main flow of water being effected by means of a pump 60. The' rate at which water is circulated by the pump 60 is controlled in accordance with the temperature of the water passing to this pump by controlling the position of a valve 6| located in the inlet pipe 62 to the pump 60. A room thermostat 63 is provided for adjusting the temperature at which the water passing to the pump 60 is maintained and a second controller 64 which may be either manually or automatically operated in any suitable manner also adjusts the temperature at which the water is-to be maintained in accordance with the number of eggs passing through the incubator.

Referringnow to Figure 2` the circuits for controlling the valve 6| are shown in detail. The valve 6| is operated by a proportioning motor of the type illustrated in Patent 2,028,110 issued to D. G. Taylor January 14, 1936. This motor may be connected to the valve by means of the arm 66 operated by the motor and the link 61 connecting the arm 66 to the stem of valve 6|. The thermostat 63 is shown to comprise a bellows 10 provided with a suitable volatile fill which causes the bellows to expand or contract in accordance with variationsln temperature in the space in which the bellows is mounted. The bellows controls the position of a slider arm 1| which cooperates with a potentiometer resistance 12, the arm 1| being connected to an arm 13 biased into engagement with the bellows by the spring 14. The controller 64 is shown to comprise a manually operated slider arm 16 which cooperates with the resistance 11 which may have suitable indicia thereon to correspond to the number of eggs within the incubator. As stated above, this arm may be manually adjusted in accordance with the.

number of .eggs in the incubator or automatically controlled in any suitable manner. Mounted in engagement with the inlet pipe 62 which conveys the Water to the pump 60 is a bulb 80 connected by the capillary tube-8| to the bellows 82, this tube, bulb, and bellows being provided with a suitable volatile ll and the bellows 82 controlling the position of the slider arm 83 which cooperates with the potentiometer resistance 84. Upon an increase in the temperature of the water in the pipe 62 the slider arm 83 moves to the right and as the temperature decreases the slider arm will move toward the left. The R terminal of the motor 65 is connected to the slider arm 83 by means of conductors 85, 86, 81 and the center tapped resistance 88. The left side of the resistance 8B is connected to the W terminal of the motor 65` by means of conductors 90 and 9| Whereas the opposite extremity of resistance 88 is connected to the B terminal of the motor 65 by means of conductors 92 and 93. As the temperature of the water in the pipe 62 decreases the arm 83 will move toward the left thus decreasing the resistance between the R and Wv terminals of the motor 65 and thus causing the motor to move the valve towards closed position and decreasing the supply of water to the pump 60. Conversely as the temperature of the water increases the resistance between the R and B terminals of the motor will decrease and the valve 6| will be moved towards open position.

The right end of resistance 12 of the thermostat 83 is connected to the B terminal of the motor by means of conductors 98, 92, and 95 whereas the opposite end of this resistance is connected to the W terminal by means of conductors 9|, 90, and 96. The slider arm 1| is con` nected to the R terminal by means of conductors 85, 86, 98, variable resistance 99, and conductor |00. The provision of the resistance 99 in the circuit to the slider arm 1| renders this control arm less sensitive than the control arm 83 and the ei'ect of a movement of the arm 1| in response to a variation in the space temperature is to shift the control range of the arm 83. In other words, a movement of the arm 83 through a distance D has as much effect on the valve 6| as the movement of arm 1| throughout the total extent of its range. As the space temperature increases and arm 1| moves toward the right, the control range D of the arm 82 is moved toward the lefi-l and this causes the valve 6| to operate to maintain a lower water temperature. The provision of the center tapped resistance 88 insures that the length of the control range D .of the control arm 83 will be the same length regardless of the position of the control range as adjusted by the thermostat 63 as well as the potentiometer 16, 11.

The right end of resistance 11 is connected by means of conductors 93. and |02 to the B terminal of the motor whereas the opposite end of this resistance is connected by conductors 9| and |03 tothe W terminal of the motor. The R terminal of the motor is connected to the control arm 16 by means of conductors 85, |05, and variable resistance |06 which renders this control arm less sensitive than the control arm 83 and a change in the position ofv this control arm 16 acts to shift the range of the arm 83. Thus as arm16 is shifted toward the right in response to an increase in the number of eggsin the incubator, the control rangeof the arm 83 will be shifted towards the left and valve 6| will operate to regulate the flow of water to maintain the tempera- `ture of the water entering the pump 60 ata lower value. f y

It will now be apparent that the pump 60 will cause a circulation of varying amounts of water in a manner to maintain the temperature of the water passing to the pump at a desired value and which value is decreased as the temperature of the space in which the incubator is located is increased or as the number of eggs in the incubator increases, and this water temperature will increase as the space temperature decreases or 'the number of eggs in the incubator decreases. The effectiveness of the control arms 1| and 16 may be readily varied by adjusting .the variable resistances 99 and |06.

The motor 65 also operates an arm ||0 carrying a mercury switch which is in the circuit to the pump 60 and causes this pump to stop should the valve 6| move to a substantially closed position Where heat transfer would be ineffective. Line wires |12'and ||8 connected to a suitable source of power (not shown) are provided for supplying power to the pump and to many of the other control devices as will be understood. When the mercury switch is in circuit Aclosing position power is supplied to the pump 80 by way of the following circuit: from the line wire 'H2 through conductors |15, H6, H1, switch conductor H8, pump 60, conductors H9, H0, 02|, and G22 to the line wire M3. When the valve 8| has been'moved to closed or substantially closed position the switch will be tilted to open position and the above described circuit to the pump 60 will be interrupted and the pump will stop operating.

The cooling and heating of the water used in the system is effected by a refrigeration system which is shown to comprise a compressor |30 driven by a. motor |3|, the compressor being connected by a pipe |32 to a condenser |33 from which refrigerant flows by way of pipe |38 and expansion valve |35, which is illustrated as a conventional type of thermostatic expansion valve, to the evaporator |36, the refrigerant returning by way of the pipe |31 to the inlet of ring again to Figure 2 the control system for the operation of the compressor |30 is illustrated in detail. Located near the exit ofthe incubator is a thermostat |39 which operates a step controller generally designated at |4|. The thermostat |39 is shown to comprise a bulb |40' connected by the capillary tube |42 `to the bellows |43, these elements being provided with ka'sultable volatile ll and the bellows controls the po.- sition of the slider arm |44 which cooperates with resistance |45 for controlling the position of the proportioning motor |46. 'I'he shaft |41 of motor |46 controls the position of a cam |48 for a purpose to be later described and a second cam |50 controlling the position of a mercury switch I| which controls the compressor operation in cooperation with switches |52 and |53 which respond to the pressure on the'suction side of the compressor.

The position of the switch |52 is controlled lower value such as '95 by'the bellows |55 which `is in communication with the pipe |31 leading to the suction side of the compressor and the position of the switch 53 is controlled by the bellowsv |56 whichis also in' communication with the pipe |31. The switch |52 is arranged to be moved to circuit breaking position when the suction pressure falls below 60 lbs. for example whereas the switch 53 remains closed until the suction pressure falls to some lower value such as 32 lbs. For controlling the operation of the compressor motor |3|, relays |58 and 59 are provided, energizationpf `either relay causing operation of the compressor motor as Will become apparent. The relay |58 comprises a relay coil |60, an armature |6I, and a switch arm |62 cooperating with a xed lcontact |63. When the relay coil |60 is energized, the arm |62 is moved into engagement with the contact |63, and when the coil is deenergized the arm moves out of engagement with the Contact under the iniluence of gravity or any suitable biasing means (not shown). The relay |59 comprises the relay coil |65, armature |66 vand switch arms |61 and |68 cooperating with the fixed contacts |69 and 10. These arms are arranged to engage their respective contacts when the relay is energized and to move out of engagement therewith upon deenergization of the relay. Power is supplied to these relays by means of a step-down transformer 1| which transformerincludes a high tension primary |12 connected across theline wires |13 and |14 leading to a suitable source of power (not shown), the 'transformer also including a low tension secondary |15.

The cam |50 controlled by the step controller |4| in response to Variations in temperature in following circuit: from the line wire |14 through conductor |82, switch arm |62, contact |63, conductors |83, |84, motor |3|, and conductor |85 to the line wire |13.' The compressor will now be placed into operation and will continue operating as long as the temperature at the bulb |40 is above 98, until the suction pressure on the compressor drops below a predetermined value such as 60 lbs.

Should the temperature in the incubator at the bulb |40 now drop below 98 the cam |50 will be rotated counterclockwise and the switch I5|y will move back to the position shown. If the temperature in the incubator adjacent the exit thereof at the bulb |40 drops to a still F. which will normally happen only when there are very few or no eggs in the latter stages of the incubator, the cam |50 will be rotated counter-clockwise still further until the mercury switch I5| is tilted to a position wherein the contacts at thewright end thereof are bridged by the mercury element. The suction pressure at this time von the compressor will normally be relatively high so that the switch |53 which moves in response to suction pressure f will be in closed position. A circuit will now be one side of the transformer secondary the space moves in a clockwise direction upon a v rise in temperature and if the temperature in the incubator rises to 98 F. at the location of the bulb |40, the cam moves the mercury switch |5| into a position wherein the contacts at the left end of the switch are closed by the mercury element. If the suction pressure on the compressor is at lbs. or above, the relay |56 will be energized at this time by means of the following circuit: from one side ofthe transformer secondary |15 through conductors |16, |11, the contacts at the left end of the mercury switch I5|, conductor |18, switch |52, conductor |19, relay coil |60 and conductor |80 to the other side of the secondary |15. Energization of the relay |58 causes switch arm |62 to move into engageestablished to the relay coil as follows: from |15 through conductor |16, the contacts at the right end of the mercury switch |5|, conductor |85, mercury switch |53, conductor |86, relay coil |65, and conductor |81 to the other side of the secondary |15. Energization of the relay |59 will cause switch arm |61 to move into engagement with the contact |69, thus establishing the following circuit to the compressor motor 3|: from line wire |14 through conductor |90, switch arm |61, contact |69, conductors |9l, |84, motor i3| and conductor |85 to the line wire |13. The compressor will now start operating and will continue to operate until the suction pressure drops to a predetermined low value such as 32 lbs. whereupon the mercury switch |53 will be moved to circuit breaking position and the compressor will shut down. The switch |53 may be arranged with a relatively wide dierential by any suitable means well known in the art so that it will not move back to circuit making position until the suction pressure has risen to some value such as 50 lbs. After the suction pressure has risen to this value and the switch |53 has moved back to this position the compressor will again operate until the suction pressure drops below the predetermined low value of 32 lbs. for example. 'I'his operation of the compressor will continue in this manner as long as the temperature at the bulb 40 remains below 95 F.

The tank 256, Figure 1, in which is mounted i the evaporator |36 surrounded by a heat exchange medium such as water, is provided with a coil in suitable heat exchange relationship with the evaporator coil |36 and heating uid is arranged to be circulated through this coil whenever the relay |59 is energized, the flow of heating medium through this coil being under the control of a valve |96. Any suitable means such as a solenoid |91 may be provided for controlling the.

mercury line wire I I2.

from the line wire |14 through conductor |98, switch arm |66, contact |I conductor. |99,

solenoid |91, and conductor 200 to the line wire It will -now be seen that whenever the compressor motor |31 is placed in operation by reason of a low temperature at the controller |39, the valve |96 is simultaneously opened thus permitting the flow of heating medium through the heat exchanger coil |96 and thereby heating the evaporator |36. Sincethe solenoid |91 is controlled by the relay |59 this valve will remain closed whenever the relay |59 is deenergized so that when the compressor is in operation by reason of the temperature at the controller |39 being above 98 F. no heating medium will be supplied to the coil |95. The purpose of this arrangement will become apparent as the description proceeds.

The cam |46 of the step controller |4| controls the position of a mercury switch 240Which is shown as being a double ended switch and in the positionillustrated, the contacts at the right end thereof are closed. In this position of the switch the valve 24| which is located in the pipe connected to the outlet of the pump 60 will be energized through the following circuit: from the line wire H3 through conductor 245, the contacts at the right end of switch 240, conductors 246, 241,V

valve motor 243, conductors 249 and 250 to the The energization of the valve motor 246 which may be in the form of a solenoid or any other suitable form of motor causes valve 26| to move to open position. As the temperature in the incubator increases cam |43 will ro tate in a clockwise direction and when the temperature has risen sumciently the cam will move the switch to its opposite position wherein the above described circuit to the valve motor 243 is interrupted and this valve 24| will close under the influence of gravity or any suitable biasing means. As shown in Figure 1 this valve is lothe motors 211, 219, and 219,y respectively, these thermostats comprising bellows, slider arms and potentiometer resistances similar to the thermostat |40 described above. Should there be a need for cooling in the last stage 26 of the incubator, the thermostat 262 will cause the valve motor 219 to move the valve 216 to open position, the opening of the valve depending upon the rise in temperature in this stage above the desired value.

Water will now be permitted to circulate through the coil 56 by the pump 60 by way of pipesr 290, 29|, 292, 293, and 294, the water leavingv this coil 55 by way of pipe 295. Connected to the pipe 295 is a pressure responsive device 300 which includes a bellows 30| controlling the position of a mercury switch 302. -As thepressure in the pipe 295 increases due to the flow ci water through the coil 56 the pressure controller 300 Will move the mercury switch 302 to closed position and in this position the motor controlling the valve 305 will be energized by way of the following circuit: from line wire ||2 through conductors 306, 301, 306, switch 302, the motor of valve 305, conductors 309, 3l0, 3| l, |2|, and |22 to the line wire ||3. Accordingly the valve 305 will now open land permit the'water to ow through this valve which is connected a pressure controller 3|1 sim# ilarto the pressure controller 300 in the pipe 295. This pressure controller will now move the mercury switch 320 controlled thereby to closed position and close a circuit to the motor of the valve 322 which circuit is as follows: from the line wire ||2 through conductors 306, 301, 323, switch 320, conductor 324, the motor of valve 322, conductors 325, 3|0, 3| I, I2|, and |22 to the line wire ||3. The water now Aflows through the valve cated in a by-pass around the cooling coil 255 in in the tank 256 surrounding the evaporator |36 serves .this purpose. When the valve 24| is closed water may circulate from the pump through the cooling coil 255 and be cooled thereby but when the valve 24| is opened the water may by-pass this cooling coil and not be cooled appreciably thereby. The mercury switch 240 also controls the position of a pair of valves 260 and 26| for a purpose to belater set forth. These valves are'shown 'as being operated by motors 262 and 263, respectively. With the mercury switch in the position wherein the contacts at the left end thereof are closed, these valve motors which are connected in parallel by conductors 265 and 266 are energized as follows: from the line wire ||3 through conductor 245, switch 240, conductor 261, Valve motors 26| and .262, and conductors 210 and 250 to the'line-wire I|2.

The ow of cooling water into the coils 54, 55, and 56 is controlled primarily by the valves 214, 215, and 216, respectively, the position of these valves being controlled by the proportioning motors 211, 218, and 219, respectively. Thermostats 230, 29|, and 232 located in the stages 24, 25, and 26, respectively, control the positions of 755 coil 53 by way of the pipe 35|. Should the tem- 322 and by way of the pipe 330 into the coil 54 and leaves the coil by way of the pipe 335'to which is connected a pressure controller 336 which controls the position of the mercury switch 331 and closes upon ow of water through the pipe 335 to cause the opening of the valve 340 by way of the following circuit: from the line wire ||2 through conductorsl 306, 34|, switch 331, conductor 342, the motor of 'valve 340, conductors 343, 3| |2|, and |22 to the line wire ||3. It will accordingly be seen that upon a call for coolingin the last stage of the incubator 'valve 216 is opened' and water iiows through'the coil 56, causes the opening of valve 305 by the pressure controller 300 `This valve is controlled by the thermostat 360 responsive to the temperature in the stage 23 and the motor controlling the position of this valve 350 will be energized whenever the temperature in the stage 23 drops to a predetermined value, thus causing the closing of the mercury switch 362 controlledthereby. When this switch closes the motorized valve 350 is energized as follows: from the line wire ||2 through conductor 365, mercury switch 362, conductor 366, valve 350, and conductors 361 and |22 to the line wire I3. Thus whenever there is no need for cooling in the stage 23 the valve 350 is open and water by-passes the cooling in the stages 24 and 25 and consequently the ow of water from coil 56 through coils 55 and 54 will be desirable.

The water leaving the coll 53 or by-passed around it may flow through the coil 310 in the condenser |33 by way of the pipes 31| and 312 or may by-pass this coil should the valve 313 be in open position. This valve as well as the valve 314 is controlled by the thermostat 315 located in the stage 22. The thermostat 315 controls a double ended mercury switch 316 and when the temperature in the stage 22 is sumciently low a circuit to the valve 314 will be energized as follows: from the line Wire ||3 through conductor 380, the terminals in the left end of switch 316, conductor 38|, valve 314, conductors 382, 383, and 384 to the line wire ||2. This valve accordingly will permit uld to flow to the coil 52. The valve 313 in the bypass around the coil 310 however will be deenergized and will prevent ow of water through this by-pass. Accordingly the water leaving the stage 23 or flowing around this stage will ilow throughthe coil 310 in the condenser |33 where it will be heated thereby and will then iiow by way of pipe 312 and valve 314 through the coil 52. At this time the valve 400 in the by-pass around the coil 52 will b e closed since the circuit thereto will be interrupted at the pressure controller 40|. However, should the temperature in the stage 22 be suiiiciently 4high the valve 313 will be energized as follows: from the line wire ||3 through conductor 380, the right hand terminals of mercury switch 316, conductor 408, motor of valve 313, conductors 409, 403, and 402 to the line wire ||2. At the same time the circuit through the valve 314 is interrupted by the mercury switch 316 and this valve will move to closed position. Pressure will now build up in the pipe 312 and the pressure controller 40| will tilt the mercury switch 404 to closed position and close a circuit through the valve 400 as follows: from the line wire ||2 through conductors 402, 403, switch 404, conductor 405, valve 400, conductors 4|2, 4|3, and 4|4 to the line Wire I3. Accordingly the water is permitted to by-pass the coil 52 in the stage 22. The same mode of operation will take place in the stages 2| and 20, the thermostat 4|5 in stage 2| controlling the valves 4|5 and 4|1 and the thermostat 4|8 in the stage 20 controlling the valves 420 and 42|. Likewise the valves 422 and 423 in the by-passes around the coils 50 and 5| will be controlled by the pressure controllers 424 and 425, respectively. The coils 50 and 5| will receive uid from the coils 43| and 430, respectively, in the condenser |33 should the valves 42| and 4|1 be closed, respectively, due to the temperature in the respective stages being at too low a value.

It will accordingly 'be seen that in the first three stages of the incubator, namely, stages 20, 2|, and 22 heating iiuid will be supplied to the coils 50, 5|, and 52, respectively, by Way of the coils 310, 430, and 43| in the condenser |33. Whenever the temperature in any one of these stages rises to the desired value the heating uid will by-pass the stage and will also by-pass the respective coil in the condenser |33. The water flows back to the pump 60 by way of the pipe 62, under the' control of valve 8|, the operation of which has been heretofore completely described.

Referring back now to the stages 23, 24, 25, and 26 which will at times require cooling, it has been stated that thermostat 232 controls the position of the motor 219 which controls the position of the valve 216 in accordance with the temperature in the stage 26. In a similar manner the valves 215 and 214 control the direct supply of water from the pump 60 through the stages and 24 in accordance with the temperature in those stages. The motor 219 which controls the position of valve 216 also controls the position of a mercury switch 450 which controls the energization of a pump 45|. Should the temperature in the stage 26 become excessively high and valve 216 moved to wide open position, the switch 450 controlled by the motor 219 will move to closed position and energize the pump 45| by way of the following circuit:

from the line wire ||3 through conductors |22,

|2I, |20, 452, 453, 454, switch 450, conductor 455, pump 45|, conductors456, 451, 459, ||6, and ||5 to the line wire ||2. will now be energized and will cause an increase in the ow of cooling water through the cooling coil 56 which will assist in -maintaining the temperature in this stage at the desired value. Pumps 460 and 45| are provided for similarly increasing the ow of water through the coils of stages 25 and 24. As the temperature in these stages becomes high, it will now be seen that the valves 214, 215, and 216 will be controlled in laccordance with the temperatures in the spaces 280, 28|, and 282 and whenever the temperature in any one of` these stages becomes excessively high, or whenever the valves are moved to wide open positions, the pumps associated with the respective stages will be placed in operation to increase the circulation of water through the cooling coils of "fle respective stages to assist in reducing the temperature thereof to the desired value. Check valves 491, 498, and 499 are provided inthe pipes connected to the outlets from pumps 45|, 460 and'46l, respec-` tively, to prevent back flow through the pumps when they are not in operation.

.There may be times when it is necessary to effect heating in the stages 20, 2|, and 22 while no cooling is required in the stages 24, 25, and 26. If no cooling is required in these latter stages the valves 214, 215, and 216 will be closed and accordingly a pipe 4154 is provided between the discharge side of the pump 60 and the pipe 35|, and this pipe 415 is provided with a pressure relief valve 416. If the valves 214, 215, and 216 are all closed, the pressure built up in the pipe 415 by the pump 60 will cause the valve 415 to open and -will permit a, circulation of water through that portion of the system which supplies water to the coils 50, 5|, 52, and 53. If any one of theses stages should be calling for a circulation of water through the coils thereof, the valves associated with those stages will be operated in the manner described above to permit this circulation of water. If cooling should be required in the stages 24, 25, or 26 at a time when no heat is required in the rst stages of the incubator, the valves associated with these rst stages will permit the water to by-pass the coils therein while at the same time the water is able to ow through the coils associated with the latter stages of the incubator.

It lmay sometimes happen that the temperature of the outlet end of the incubator will drop to a relatively low value, this occurring under-` time the compressor will be placed in operation under the control of the suction pressure controlley,- -ltt as heretofore described to maintain the suction pressure at a. relatively low value but it should be suihciently high so that freezing or water or heat exchange medium surrounding the evaporator itt will not take place. IDuring operation oi the compressor under this condition the valve -liit is opened as heretofore described to permit the supply of heating mediumlto the heat eircl'ianger` coil l95 thus adding heat tothe evaporator itt and thereby imposing acooline load thereon so that longer compressor operations'will take place before the suction pressure wllldrop to the cut-out value and so that more heat will be given oi by the condenser itt, which heat equivalent is of greater value than the heat delivered to the coil let,A and which'heat,

in the condenser |33, may also be at a higher temperature level, if the heating medium` supplied to the coil |95 is relatively cool, such as where well water or other low temperature medium is supplied thereto. In this manner, the refrigeration system will operate even if the temperature at the outlet end of the incubator drops lto a relatively low value so as to supply the necessary heat to ythe incubator during the early stages of incubation.

As stated above, when lthe'valve 2M is closed due to the existence of a high temperature in the incubator, thus causing the water to flow through the coil 255 associated with the evaporator of the refrigeration system, the valves 26u and 26| will be opened by the step controller and water-.will be permitted to ow through the coil it associated with the condenser of the refrigeration system. 'Ihis water will ow from the pipe 293 through pipes ilil, @82, i833 into the lower part of the coil itil and will leave the upper part of the coil through pipes ist and litt. A branch pipe ist supplies water from the upper crease and this in turn will cause an increase in the head pressure on the-compressor |30.

. Associated with the outlet of the compressor is a pressure responsive device 500 which comprises a bellows connected to the discharge from the compressor by means oi pipe 602, the bellows controlling the position of the mercury` switch B03. Whenever the discharge pressure on the compressor rises sumciently high, which will be an indication that the refrigeration system is doing an excessive amount of cooling` and that it will be advantageous to cool the condenser, the switch 503 will be tilted to the circuit making position thus causing the energization of the pump M5 by means of the following circuit: from the line wire lli through conductors 505, mercury switch 503, conductor 508, pump M5, and conductor 501 to the line wire H3. At this time therefore the pump M5 will be placed into operation and `will cause a circulation of water through the coil d8@ and the cooling tower tot to thus cause cooling of the condenserv by the coil itil, thereby reducing the head pressure on the compressor itil. Whenever the heating load on the system rises sumciently however, sumcient heat; will be extracted from the condenser bythe coils 3W, i3, and 33| so that it will be lundesirable to cool the condenser by means of the coil t8@ and the cooling tower M8 since all the heat of the condenser will be requiredV for heating purposes and this increase in the heating load on the system will be reected by a drop in the head pressure on the compressor.

In the chamber 38 is a dehumidifying coil till through which cooling medium may be supplied to reduce the dew-point of the air passing thereover and entering the system during times when the humidity of the supply airis excessive.

. from the tank 256 associated with the evaporator part of the coil #itt to a spray ttl located in a cooling tower i388. Air may ow upwardly through this cooling tower to cool the water spray, the air entering through the inlet M9 and leaving through the outlet opening t9@ in the top of the tower. This cooling tower is provided with an outlet pipe itl for preventing the level oi the water in this tower from rising above a pre` determined value so that if sumcient water ac cumulates in the bottom of the cooling tower,.

It@ by means of the pipe 5|6, the cooling medium then passing through the pipe Sl'l to the coil dit and returning by way of the pipe 52d to the tank 256. The supply of cooling medium to the coil Bill will depend upon the operation of the pump M5 andthis pump will be operated in accordance with the humidity in the incubator.

For controlling the pump SI5, a humidity responsive device 525i is located within the incubator or may be located in the exhaust air duct,

it will flowv out through the pipe tol. A pump dat is also' provided fordrawing water from the bottom of the cooling tower and feeding this water back to the coil. {itil} associated with the condenser itt by way of pipes litt and dat so that when this pump is in operation there will he a continuous circulation of water from 'the cooling tower' through the coil fitti, thus eecting a re-n duction in temperature of the condenser. When the system requires a greater amount of heating than it does of cooling by the refrigeration system, it will be undesirable to operate the pump dtd sincethe condenser heat will be needed for heating the coils et, ai, and. 52. However, during periods when the refrigeration system is doing a greater amount of cooling than itis oi heating, the temperature of the condenser will in" and this device comprises a hygroscopic' element dit which controls the position of a lever 521 in accordance with the humidity in the space. As the humidity increases, the'hygroscopc element [6211i will elongate and the lever 527 will be moved in a counter-clockwise direction by means of the biasing spring 528, and upon a decrease in hu midity the element 52H5 will contract and the lever 5527i will move in the opposite direction. The lever 52T carries a pair of mercury switches 53K! and titi and these switches are so arranged, as will be apparent from the drawing, that as the humidity risesto a certain value the switch ttl will be moved to closed position and as the humidity decreases to a predetermined value the switch 535i will move to closed position. When the humidity in the incubator rises suciently high that switch lidi is closed, a circuit is established to the pump lll as follows: from the line wire iid through conductor 535, switch` iltli, conductor i536, pump die, and conductors ttl and llt to the line Wire i l2. lt will thus be seen that when the humidity in the incubator becomes sufnciently high that the pump tit will operate to This. coil is supplied with cooling medium by means pump cooling medium through the coil I8 which will cause a reduction in the dew-point of the air entering the incubator by way of this coil.

Also located within the chamber 38 in a spray 548 which may be supplied with water under the control of the valve 54| from a supply pipe 542 when the humidity inthe incubator becomes suiliciently low. When the humidity in the incubator drops sumcientlythe switch 538 will move to closed position and close a circuit through the motor controlling the position of Valve 54| as follows: from the line wire H3 through conductor 545, switch 588, conductors 546, 541, valve 54|, and conductors 546 and 549 tothe line wire H2. Accordingly, the valve 54| will be opened and the air entering the inclbator and passing by this pipe 548 will receive moisture by way of this spray and accordingly its humidity will be raised. A tempering coil 552 is located below the spray 548 so that when the air entering the incubator is in need of humidiication, which will generally be at times when the outside air is at a relatively low temperature, this air may have its temperature increased by the coil 552 so that it will be able to absorb additional moisture from the spray 548, and this coil 552 receives water from the pipe 48| and the pipe 555 and the water is returned to the pipe 485 from the coil 552 by way of the pipe 556. The iiow oi water to the coil 552 is under the control of a valve 568 which is normally closed and opened only when the valve 54| to the spray 548 is opened indicating a need ofy humdification. It will be noted from an examination of Figure 2 that the valve 568 is connected to the line wires I |2 and H3 through the switch 538 in parallel with the valve 54| by means of conductors 56| and .562 and it will accordingly be apparent that the valves 54| and 568 willbe simultaneously opened and closed.

The bottom of the chamber 38 is provided with a sump to receive water from the spray 548 and this sump is provided with a pair of outlets 565 and 566 which lead to the spray 561 and the spray 568, respectively. The ow of water to the spray 568 which is located in the chamber 35 is controlled by a valve 518 and the spray 561 is always in communication with this sump in the chamber 38 through the pipe 565. The air leaving the incubator passes downwardly through the chamber 4| over the heat exchanger 48 as has been pointed out above, and before this air passes outwardly through the opening 42 it must pass over the spray pipe 561 which spray will be rather cold under normal conditions since the spray 548 is only operating at those times when there isa need for humidiiication which will more often occur in cold weather. The air leaving the incubator gives up a greater portion of its heat to the air entering the incubator by means of the heat exchanger 48 but this air may still be considerably above the temperature of the spray 561 and accordingly the spray 561 will be able toextract a large amount of heat from the outgoing air. This water which has now been warmedpby the outgoing air ows by way of a pipe 516 into the coil 36 which is located in the chamber 35 and is provided for further preheat- `ing the air entering the incubator, the water leaving this coil by way of pipe 511 and passing into the chamber 488, thus forming an additional supply of water for the cooling tower 488. It will accordingly be seen that while the outgoing air gives up a large portion of its heat to the air entering the incubator by way of the'heat exchanger 48, further heat is extracted from this air and given to the incoming air by means of the spray 561 and the preheating coil 36. In 0 F. weather, the water owing to the spray 568 will be about 60 F. and the water flowing through pipe 516 to the coil 36 will be about '75 F.

The valve 518 which controls the flow of water to the spray 568 is controlled by the thermostat 588 which comprises a bulb 58| located in contact with the pipe 511, this bulb being connected by means of a capillary tube 582 with a bellows 583, this bellows controlling the position of a slider arm 585 which moves over a potentiometer resistance 586 in accordance with variations in the temperature of the water iiowing through the pipe 511. The slider arm and potentiometer form a control means for the motor 598 which controls the position of the valve 518, this motor being a proportioning motor of the type described above so that the position of the valve 518 will vary in accordance with the temperature of the water leaving the coil 36. If the outside temperature is excessively low and a large amount of water must be added to this air for humidication purposes, it may be necessary to further raise the temperature of the air passing to the spray 548 so that when the temperature of the water leaving the coil 36 drops the valve 518 will begin to open permitting water to flow from the spray 568 to further raise the temperature of the air and increase the amount of moisture absorbed thereby.

Should the supply of water to the cooling tower 488 by way of the pipe 511 be insuiiicient, water may also be supplied thereto by way of the pipe 688 connected to a source of water by way of the pipe 542. A oat Valve 68| cooperates with the outlet of the pipe 688 to control the flow vof Water therethrough into the cooling tower in a manner to maintain the level of water therein at a predetermined value.

During periods when dehumidication of the air is required and cooling fluid is being circulated through the coil 5|8 to lower the dew-point of the air, moisture will collect on this coil and this moisture is drained therefrom -by means of the pipe 685 which conducts this water into the sump in the bottom of the chamber 38.

If the temperature of the air entering the cooling tower 488 is excessively low, the air in chamv ber 4| leaving the outlet 42 may be conducted to the inlet 489 of the cooling tower 488 since this air will always be at a relatively high value such as 50 F.

Referring now to Figure 3, the means for causing automatic ejection of sterile eggs at a predetermined time-during their passage through the incubator will be explained. This egg ejecting meansis preferably located at a point which the eggs will reach shortly after their third day in the incubator and this means includes an arrangement utilizing a photo-electric cell for determining the fertility of the eggs. Located above the incubator is a series of incandescent lights 658, there being one light for each row of egg compartments on the belt H although for purposes of illustration only one has been illustrated, and on the opposite side of the belt is a photo-electric cell 65|. Lenses 652 and 653 are located on opposite sides of the belt and between the lights 658 and the photo-electric cells 65| to direct the rays of light from the light source to the photo-electric cell as shown by dotted lines in Figure 3. When light passes from the light source 653 to the photo-electric cell 65|, current is supplied to the amplier 655 in a manner Well current to a solenoid 656 at such times, the supply of current to the solenoid also being under the control of a timer 660. This .timer comprises a cam 66| carrying a plurality of projections 662 thereon, this cam being connected for rotation.

with a sprocket 663 over which the conveyor belt passes so that movement of the cam 68| is in timed relation with the movement ofthe conveyor belt. The cam 66| controls the position of a switch arm B65 which is biased` upwardly, this switch arm cooperating with a fixed contact 066 so that whenever one of the projections 662 engages the switch arm 665, the switch arm will be moved into engagement with the contact 660. Ihis switch arm is arranged to be moved into engagement with the contact 666 only when the eggs carried by the belt Il are in a position to intercept the beam of light between the lamp 650 and the photo-electric cell 65|. If the egg is fertile it will permit the passage of relatively little light 'therethrough after the third day of incubation because of the embryo chick therein. Should the egg be sterile. however, sufilcient light will pass through the egg so that the photo- 'electric cell will cause the venergization oi the solenoid 656.

Referring now to Figure 5 wherein is illustrated a fragmentary portion of the conveyor belt, the conveyor belt comprises a pair of sprocket chains 610 on either side thereof, only one of such chains being shown. The sprocket chains comprise a plurality of interconnected links as is conventional and some of the pivots 611 for these links are extended as rods 612 so that the two sprocket chains are interconnected by means of a series of these rods. Rotatably carried by these rods as by means of the rings 618 are a plurality of egg carrying members 615 which may be made of anysultable porous light transmitting material such as a foraminous screen, these supporting members being biased upwardly by means of the springs 616 into lthe plane of the belt. The supportingl members may be limited in their upward movement by engagement of the spring 616 with the wall member 680 described below, or in any other suitable manner. Suitably carried by the rods 612 are the partitions I5, shown in Figure 5 as the wall members 680, which together with the supporting members 615 form separate compartments on the conveyor belt which separate each egg on the belt from the other eggs thereon. The wall members at one edge of the belt may be U-shaped as shown in Figure 5 thus surrounding three sides oi the egg and this Urshaped member cooperates with the next U-shaped member to`form the fourth side of the compartment as clearly shown in Figure 5. 'I'he remaining compartments widthwise of the belt may be formed simply as L-shaped members 682, each L-shaped member cooperating with a similar member vfor another compartment to form the four upstanding Walls of the compartment and in this manner each egg is separated from every other egg on the belt by these upstanding wall portions so that as air is circulated upwardly through the belt, no two eggs being carried thereby will be contacted by the same portion of air. These upstanding wall portions are carried by the rods 612 independently of the supporting screens 619 so that movement of these screens around the rods 612 as an axis against the force of the biasing springs 610 is permitted.

Each of the screen members 61! supporting Ibe made of soft iron for example and will be attracted by the armature 686 of the 'electro-` magnet 866 when the magnet is energized. Upon energization of the magnet, the soft iron pieces 686 will be attracted to the armature 686 thus causing the screens 615'to pivot downwardly and permitting the eggs to roll out of the belt il.

Supported below the belt is a guideway I0 suitably located so that when the supporting members 616 are pivoted downwardly under the influence of the electromagnet 666 the eggs will roll into this runway I9 and will roll out of the incubator where they may be gathered and disposed of as desired. s y

It will now be seen that at predetermined intervals the switch arm 665 will be moved into engagement with the contact B80, it being understood that there is a separate switch arm and contact similarly operated for each row of egg compartments on the belt and if the light from the light' source 850 passes through the respective eggs on the belt, which will happen only it the eggs are sterile, current will flow through the respective amplifiers 656 through the electromagnet 656 by means of conductors 610, switch arms 666, contact 666, conductor 61|, coil 656 and conductor 612 to the amplifier 655, power'lbeing supplied to the amplifier by means of line wires 005 and 606 connected to any suitable source of power (not shown). If this circuit were not interrupted periodically by the timer 660 the light would pass fromthe source 650 to the photoelectric cell 66| when that portion of the belt ldirectly back of the egg were between the light move through the incubator after the third day,

for example. y

Attention is now directed to Figure 6 which shows one suitable form of belt cleaner and puriier through which the belt passes after leaving the incubator so that the portion of the belt entering the incubator is always maintained in a. clean and pure condition. The belt passes from the exit end of the incubator into a tank 100 containing a supply of cleansing and sterilizing fluid 10|, this fluid being continually changed by means of a pump 102. The fluid from the tank 100 flows through a pipe 103 into a receptacle 104 having its top portion in communication with the pump inlet by meanse of a pipe 10B. A screen 106 is interposed'between the pipe '|03 and the pipe 105 to prevent any dirt particles from entering the pump 102. The pump discharges the fluid which has now been relieved of its dirt partlcles into a purifier 106 which may be of any suitable construction and may` take the yform of an ozone generator through which power is supwith a clean-out door 1|2 so that accumulated dirt on the screen 106,'may be periodically removed, there |being a shut-off valve 1|5 in the pipe 103 so that the ow of uidintothefreceptacle\104 may be shut off atl such time. y

Located above a horizontal run of the belt 1li is a beater 120 of any suitable construction and may be provided with suitable, flexible beating members 12| whichmay bel formed of leather. or other suitable material, the beater 120 being yconnected by means of the belt 122 to a motor 123 to cause rotation of thev same. The beating g elements 12| cause a continual beating action on the back of the belt so that any loose foreign mattersuch as egg shells or the like willbe removed and fall into a guide 125 whence they will pass into a suitable receptacle 12. In this manner the belt is removed of the majorityrof foreignmatter prior to entering the cleaning receptacle 100. 'I'he motor 123 also drives by means of the belt 128 a brush 130 having suitable bristles for engaging the back of the belt in the tank 100, thus imparting a scrubbing action to the belt and completely removing all remain-- ing foreign matter therefrom and since the liquid within the receptacle 100 is continually cleansed and sterilized it will be apparent that the belt as it leaves the receptacle will be in a clean and purified condition.

To summarize brieily the operation of the system of Figures 1 and 2, it will be seen that a supply of fresh air is being continually circulated through the incubator although this supply may be relatively small, the air flowing upwardly over the heating or cooling coils, passing through the conveyor belt and passing outwardly from the incubator through the upper wall thereof, this circulation of air being eiected by the fan 33. The Walls of the incubator are kept at desired temperatures in the various stages and in this manner the eggs on the belt will be maintained at desired temperatures which might be 100 F. in the first "six stages of incubation and 98 F. in the last 'stage of incubation or the hatching stage. Since in some stages of incubation the eggs will require heat in order to maintain them at the proper temperature and since in the latter stages the eggs Will be generating a large amount of heat, it will be necessary to remove some of this heat in these latter stages. The heat given up by the eggs in the latter stages of incubation is conducted to the first stages of incubation by' means of the water circulating through the various coils imbedded in the walls of the incubator.

The pump 60 causes water to circulate through the desired coils, the ilow of Water to the pump being controlled by the valve 6|, and this valve is operated to circulate a' suilicient amount of water so that the water passing to the pump will be maintained at a desired temperature which temperature will be variable depending upon the number of eggs in the incubator and the temperature of the space in which the incubator is located. Thermostats in the various stages of the incubator control the supply of water to those stages in a manner to maintain the temperature therein at the proper values and when the incubator temperature rises sufiiciently high, indicating a need for considerable cooling in the latter stages of incubation the cooling fluid is cooled by circulating this water in heat exchange relationship with the evaporator of a refrigeration system by closing the valve 24| in the by-pass to the coil 255. The water for heating the coils in the early stages ofdncubation is heated by passing through coils which are in heat exchange relationship with the condenser of the refrigeration system should heat be necessary in the early stages of incubation. Since the water transfers the heat from the incubator in the latter stages of incubation to the early stages-of incubation, it

' ywill normally be unnecessary to further cool or heat the water to any considerable extent and it 10 is therefore possible to utilize a refrigeration system of relatively small capacity for supplying the necessary heating and cooling to the various coils' in the incubator.

The various heat exchangers by which the heat of the outgoing air is given up to the incoming air further increase the operating eiilciency of the system and a large part ofthe available sensible andlatent heat leaving the incubator is imparted l to the air entering the same.

'Ihe cooling tower 488 operates to cool the condenser |33 during periods when the refrigeration system is being utilized to eiect a larger amount of cooling than heating and in these instances theY head pressure on the compressor will increase and the pressure controller 500 will operate the pump 095 to circulate cooling duid through the cooling tower 080 and the .cooling coil 480, the valves 260 and 25| being open at this time by the step controller |4| which causes these valves to open when suiiicient cooling of the latter stages of the incubator is necessary.

The compressor |30 is controlled by the switch |5I of the step controller Ml in such a manner that when the temperature adjacent the outlet of the incubator is above 98 F., for example, the

compressor operates to maintain a suction pressure of 60 lbs. for example. Between 95 and 98 F.' the switch |5| will be in open circuit position and the compressor will be shut down. Should the temperature at the controller |39 dropto a still lower value such as 95, the compressor will operate to maintain a lower suction pressure and at the same time heat will be supplied by the coil |95 to the evaporator |36 thus loading the compressor so that sufficient heat will be generated in the condenser |33 to produce the necessary heat for the early stages of incubation, it

Ybeing understood these conditions will not occur under normal circumstances but only when there are relatively few or no eggs on the belt Il in the latter stages of incubation.

During periods when dehumidiiication of the air passing to the incubator is necessary by reason of the humidity within the incubator rising too high, the humidity responsive device 525 causes pump 5|5 to circulate iiuid from the cooling chamber 256 through the coil 5|0 to reduce the dew-point of the air entering the incubator. If on the other hand the humidity in the incubator falls too low, valves 54| and 560 are open, the spray 540 is operated and the tempering coil 552 is supplied with water to temper the air passing through the spray 540 whereby the temperature of the air will be raised and more water may be picked up thereby. The water from this spray 540 is utilized to absorb latent heat from the outgoing air in the chamber 4| and transform this latent heat into sensible heat oi' the incoming air passing through the chamber 35 by means of the coil 36. In excessively cold Weather the water leaving the coil 36 may have a very low temperature and the spray 568 is at this time operated by the opening of the valve 510 to increase the humidity of the air passing into the incubator.

be collected and used for a useful purpose such as the. manufacture of egg powder before they.I

have been in the incubator for too long a time. The cleaner 21 maintains the belt in a .clean and sterilized condition thus materially reducing spread of germs to the eggs on the belt.

It will thus be seen that I have provided a sys tem for controlling properconditions of temperature and humidity 1n an incubator of relatively large capacity by the use of a relatively small refrigeration system for supplying whatever heatresponds to the temperature adjacent the outlet end of the incubator.l This thermostat may be of any suitable construction and for purposes of illustration is shown as including a bimetallic element SII controlling the position of an, arm 8 I 2 with respect to a xed contact 8 I 3. When the temperature at the thermostatrises to an excesing or cooling is necessary to the incubator and the employment of such a small system is made possible by a very eflicient arrangement for utllizing the heat released by theeggs in the latter stages of incubation for heating the eggs in the earlier stages of incubation and under many conditions very little heat or cooling will be required by the 'refrigeration system since the heat given up by the eggs in the latter stages of incubation may be all that is necessary to properly heat the eggs in the earlier stages. Since the air which passes through the incubator flows upwardly through the belt ii, and since the eggs carried by the belt are al1 separated by partitions from one another, the air in the incubator is maintained in a condition of purity at all times and the circulation of air is unable to spread any germs that may be on or in one egg to another egg since there is no portion of the air that contacts more than a single egg. The employment of other means such as chemicals to reduce the germ concentration -of air in the incubator is rendered unnecessary by this arrangement and since the use of such chemicals reduces the number of chicks that are hatched yfor a given number of. eggs, the losses from unhatched eggs are considerably reduced and are also considerably reduced by reason of the fact that the temperature and humidity of the air in the incubator will be maintained at the desired value at all times.

Referring now to Figure'l, I have illustrated a simplified form of air conditioning system which would be applicable for use with smaller incubators and which embodies the principles of the system illustrated in Figures 1 and 2.l

In this figure there is no vcontrol whatever 'over the flow of water through the various coils in the dierent portions of the incubator but use is sive value, the arm 8I2 moves into engagement with contact 8I3 and energizes the solenoid 008 by means of the following circuit: from line wire 8I5, contact 8I3, arm 8I2, bimetallic element 8i I, conductor BIB, solenoid 808, and line wire 8I1.` Thus whenever the temperature adjacent the outlet of the incubator becomes excessive, the valve 801 is opened, cooling medium -is supplied to the cooler 80| whereby the heat exchanger medium being circulated therethrough by the pump 800 is cooled whereby additional heat may be absorbed from the incubator to reduce the temperature in the latter stages to the desired value.

Any suitable heating medium may be supplied to the heater 805 under control of a valve 820 the position of which may be controlled by a solenoid 82I which is under the control of a thermostat 822 located in theinlet end of the incubator, which is shown to be similar to the thermostat 0I0, the arrangement being such that when the temperature adjacent the inlet of the incubator drops to a predetermined value the thermostat 822 closes a circuit through the arm B23 and contact 820 thus energizing the solenoid 82| as.follows: from line wire 02B through conductors 820, 021, thermostat 822, arm 023, contactl 82H, conductor 830, solenoid 82I, and conductor SSI to the line wire 832. Accordingly, whenever the temperature adjacent the inlet of the incubator drops to a low 4 value indicating that insufhcient heat is being absorbed by the heat exchanger medium in the latter' stages of incubation to raise the temperature in the early stages of incubation to the deslred value, heating medium is supplied to the heater 805 so that sumcient heat will be radiated by the heating coils in the earlier stages of incubation to raise the temperature therein to the clesired value. Under normal conditions however, if the incubator is properly insulated and is substantially full of eggs, sufilcient heat may be absorbed by the heat exchanger medium in the latter stages of incubation and added to the incubator in the earlier stages of incubation to maintain temperature in all parts thereof at approxitaken of the heat absorbed by the cooling fluid circulating through the coils in the latter stages y of incubationfor supplying thev heat to the incubator' in the earlier stages of incubation as in Figures l` and 2. A pump 800 is provided for circulating the fluid through the various heat exchanger coils embedded in walls of the incubator, there being a cooler 80| located between the pump discharge and the coll in the last stage of the incubator whereby cooling of the heat exchanger medium may be effected if required. A heater is also provided between the coils 62 and 63 in stages 22 and 23 so that if insufficient heat is absorbed by the cooling medium in the latter stages of incubation to raise the temperature at the opposite end of the incubator to the required value, this may be done by the heater 806..

[A cooling medium is supplied to the cooler 80| by meansvof a pipe 806 under the control of a valve 801 which may be operated by any suitable means such as a solenoid 800, the energization of which is controlled by a thermostat 8I0 which mately the desired values. The temperature of the fluid being circulated will normally not fluctuate more than about two degrees throughout the cycle.

The heating and cooling requirements of each stage are considerably different from every other stage. For example, the first stage may take about %.of the heat and the last stage may take about 70%: of the cooling. The intermediate stages will require varying amounts of heating or cooling but very little of each. In order to carry the heat absorbed in the last stage to the rst stage without losing'it on the way, it is desirable in medium sized lncubators to proportion the heat transfer surface in each stage to Thus, the lastv there is so little heat transfer between these stages, and the water may leave the first stage at about 96 F.

Located within the incubator at a suitable location such as adjacent-the center portion thereof is a humidity responsive element 835 of any suitable construction and which controls the position of an arm 836 with respect to a pair of xed contacts 831 and 838 in -response to the humidity existing within the incubator. When the humidity in the incubator is excessive the arm 838 will engage the contact 831 and if the humidity drops l to an undesirably low value the arm 838 will engage the contact 838. When the humidity is at the desired value however, the arm 836 will be between the contacts 831 and 838 and in engagement with neither contact. This humidity responsive device controls the operation of a pair of valves 848 and 84|, the positions of which may be controlled by solenoids 842 and 843, respectively. The valve 848 may control the supply of a humidifying medium to the spray 844 Whereasy the valve 84l may control the supply of a dehumidifying medium to the spray 845. Both of these sprays are arranged in the path of fresh air entering the incubator, this air preferably passing through a heat exchanger 48 similar to that shown in Figure 1 for tempering the air prior to passing into the incubator.

If the humidity in the incubator is too low, arm 838 will engage contact 838 thus energizing solenoid 842 as follows: from the line wire 825 ductors 851 and 852 to the line wire 832. Upon energization of the solenoid 843, the valve 84| is opened and a suitable dehumidifying medium such as an hygroscopic brine is supplied to the spray 845 for reducing the humidity of the air being supplied to the incubator.

It will be apparent that While the system of Figure 7 is relatively simple and does not provide accurate control of temperature in each o f the stages of the incubator nevertheless it does embody the principles of the system of Figures 1 and 2 and does provide control of the temperature adjacent the inlet and outlet ofthe incubator and of the humidity within the incubator and such a system may provide sufflciently good control for incubators of small capacity. This arrangement will also be suitable for incubators of large capacity but since it does not give as accurate control as the system of v Figure 1, there may be a greater loss of chicks from fertile eggs than with a system of the type lshown in Figure 1. The amount of control necessary will also vary somewhat in accordance with climatic conditions in the section of the country in which the incubator is to be used.

Any suitable dehumidifying medium may be employed in the 'spray 845 and this may take the form if desired of a solution of calcium chloride, which may also be utilized in the system of Figure 1 if desired. The unit 35 of Figure 1 may also be replaced if desired by a lump calcium dehumidifier for very humid climates.

.Havingvdescribed two preferred forms of my, I invention, it will be apparent that many modi-1- ications may be made by those skilled in the art and I therefore wish it to be understood that my invention is limited only( by the scope of the appended claims. l

I claim as my invention:

1. In an air conditioning system for an enclosure having certain portions thereof normally requiring cooling and other portions thereof normally requiring heating, means for absorbing heat from those portions of the enclosure normally requiring cooling, heat delivery means for those portions of the enclosure normally requiring heating, means for circulating a heat exchange medium through the heat absorbing and heat delivery means whereby heat is transferred from those portions requiring cooling to those portions requiring heating,

paratus, means utilizing the refrigerating apparatus for removing heat from the heat exchange medium passing through those a refrigerating apportions of the enclosure requiring cooling,

means utilizing the condenser of said refrigerating apparatus for adding heat to the heat exchange medium passing through those portions of the enclosure requiring heating, and means for artificially heating said evaporator when said enclosure requires more heating than cooling.

2. In an air conditioning system for an enclosure having certain portions thereof normally requiring cooling and other portions thereof normally requiring heating, means for absorbing heat from those portions of the enclosure normally requiring cooling, heat delivery means for those portions of the enclosure normally requiring heating, means for circulating a heat exchange medium through the heat absorbing and heat delivery means from those portions whereby heat is transferred requiring cooling to those portions requiring heating, a refrigerating ap-v paratus, means utilizing the evaporator of saidl refrigerating apparatus for removing heat from the heat exchange medium passing through those portions of the enclosure requiring cooling, means utilizing the condenser of said refrigerating apparatus for adding heat to the heat exchange medium passing through those portions of the enclosure requiring heating, means for cooling the condenser of the refrigeration system, and means rendering said last means operative only when more cooling than heating is being done by the refrigeration system.

3. In an air conditioning system for an enclosure having certain portions thereof normally requiring cooling and other portions thereof normally requiring heating, means for absorbing heat from those portions of the enclosure normally requiring cooling, heat delivery means for those portions of the enclosure normally requiring heating, means for circulating a heat exchange medium through the heat absorbing and heat delivery means whereby heat is transferred from those portions paratus, means utilizing the evaporator of said refrlgerating apparatus for removing heat from the heat exchanger medium passing through those portions of the enclosure requiring cooling, means utilizing the condenser ing apparatus for adding heat to the heat exchange medium passing through those portions portions requiring cooling to those of the enclosure requiring heating, means for evaporator of said requiring heating, a refrigerating ap' of said refrigeratcooling the condenser of the refrigeration system, means rendering said last means operative only when more cooling than heating is being done by the refrigeration system, and means utilizing .the condenser cooling means for additionally cooling the heat exchange medium circulating through the heat absorbing means.

4. In an air conditioning system for an enclosure -having portions requiring varying degrees oi heating while other portions may simultaneously require varying degrees of cooling, heat exchanger coils associated with each o! said portions oi' the enclosure, means for cir- 4culating a heat exchange medium serially through the several coils so that heat may 'be absorbed from the portions ofthe enclosure requiring cooling and transferred to the portions of the enclosure requiring heating, means responsive to the temperature in each portion oi the enclosure i'or selectively controlling the flow o! heat exchange medium through the respective portions or causing said medium to by-pass said portions, refrigerating apparatus including a condenser, and means responsive to a demand for heating in any of the portions of the enclosure for causing the heat exchange medium passing to said portion to pass in heat exchange relationship with the condenser.

5. In an air conditioning system for an enclo` sure having. portions requiring varying degrees of heating while other portions may simultaneously require varying degrees of cooling, heat exchanger coils associated with each of said portions of the enclosure, means for circulating a heat exchange Vmedium serially through the several coils so that heat may be absorbed from the portions oi the enclosure requiring cooling and transferred to the portions of the enclosure requiring heating, means responsive to the temperature in each portion of the enclosure for selectively controlling the ilow of heat exchange medium through the respective portions or causing said medium to by-pass said portions, refrigerating apparatus including a condenser and an evaporator, means responsive to a demand i'or heating in any of the portions of the enclosure for causing the heat exchange medium passing to said portion to pass in heat exchange relationship with said condenser. and means responsive to the attainment of a high predetermined temperature in a portion of the enclosure requiring cooling for causing the heat exchange medium passing to those portions of the enclosure requiring` cooling to pass in heat exchange relationship with said evaporator.

6. In an air conditioning system for an enclosure having portions requiring varying degrees of heating while other portions may simultaneously require varying degrees of cooling, heat exchanger coils associated with each of said portions of the enclosure, means for circulating a heat exchange medium serially through the several coils so that heat may be absorbed from the portions of the enclosure requiring cooling and transferred to the portions of the enclosure requiring heating, means responsive to the temperature in each portion of the enclosure for selectively controlling the ilow of heat exchange medium through the respective portions or causing said medium to by-pass said portions, refrigerating apparatus including a condenser and an evaporator, means responsive to a demand for heating in any of the portions of the enclosure for causing the heat exchange medium passing to said portion to pass in heat exchange relationship with said condenser, means responsive to the attainment of a high predetermined temperature in a portion oi the enclosure requiring cooling for causing the heat exchange medium passing to those portions of the enclosure requiring cooling to pass in heat exchange relationship with said evaporator, and means utilizing said evaporator for reducing the humidity in the enclosure.

7. In an air conditioning system for an enclosure having certain portions thereof normally requiring cooling and certain other portions normally requiring heating, means for, absorbing heatfrom those portions oi' the enclosure normally requiring cooling, heat delivery means for those portions of the enclosure normally requiring heating, means for circulating a heat exchange medium successively through the heat absorbing and heat delivery means whereby heat is transferred from those portions requiring cooling to those portions requiring heating, by-pass means for said heat exchange medium around each of said portions, means for cooling said fluid. means for heating said uid, means responsive to the temperature of the portions normally requiring cooling for causing said heat exchange medium to flow through said cooling means and said heat absorbing means when cooling is required or to by-pass both ci them when cooling is not required, and means responsive to the temperature of the portions normally requiring heating for causing said heat exchange medium to flow through said heating means and heat delivery means when heating is required and to by-pass both oi them when heating is not required.

8. In an air conditioning system for an enclosure having certain portions thereof normally requiring cooling and certain' other portions normally requiring heating, means for absorbing heat from those portions of the enclosure normally requiring cooling, heat delivery means for those portions of the enclosure normally requiring heating, means for circulating a heat exchange medium successively through the heat absorbing and heat delivery means whereby heat is transferred from those portionsrequiring cooling to those portions requiring heating, by-pass means for said heat exchange medium around each of said portions, refrigerating means having an evaporator and condenser, means responsive tothe temperature oi the portions normally requiring cooling for causing said heat exchange medium to flow into heat exchange relationship with said evaporator and then through said heat absorbing means when cooling is requiredv or to by-pass both of them when cooling is not required, and means responsive to the temperature Aof the portions normally requiring heating for causing said heat exchange medium to flow into heat exchange relationship with said condenser and then through said heat delivery means when heating is required or to by-pass bo'thof them when heating is not required.

9. In an air conditioning system for an enclosure having certain portions thereof normally .requiring cooling and certain other portions normally requiring heating, means for absorbing heat from those portions of the enclosure normally requiring cooling, heat delivery means for those portions of the enclosure normally requiring heating, means for circulating a heat exchange medium successively through the heat absorbing and heat delivery means whereby heat is transferred from those portions requirheat exchange then through said heat'absorbing means, when cooling is required or to by-pass both of them when cooling is not required, and means responsiveto the temperature of the portions normally requiring heating for causing said heat exchange medium to ilow into heat exchange relationship with said condenser and then through said heat delivery means when heating is required or to by-pass both oi' them when heating is not required, and additional means i'or cooling said condenser when more cooling is required than heating.

10. In an air conditioning system for an enclosure having certain portions thereof normally requiring cooling and certain other portions normally requiring heating, means for absorbing heat from those portions of the enclosure normally requiring cooling, heat delivery means for those portions of the enclosure normally requiring heating, means for circulating a heat exchange medium successively through the heat absorbing and heat delivery means whereby heat is transferred from those portions requiring cooling to those iportions requiring heating, by-pass means for said heat exchange medium around each oi' said portions, refrigerating means having an.evaporator and condenser, means responsive to the temperature of the portions normally requiring cooling for causing said heat exchange medium to flow into heat exchange relationship with said evaporator and then through said heat absorbing means when cooling is required or to by-pass both of them when cooling is not required, and means responsive to the temperature .'oi the portions normally requiring heating `for causing said heat exchange medium to ilow into heat exchange relationship with said condenserand then through said heat delivery means when heating is required or to by-pass both oi them when heating is not required, and additional means for heating said evaporator when more heating than cooling is required.

` 11. In an air conditioning system for an enclosure having certain portions thereof normally requiring cooling and certain other portions normally requiring heating, means for absorbing heat from those portions of the enclosure normally requiring cooling, heat delivery means for those portions of the enclosure normally requiring heating, means for circulating a heat exchange medium successively through the heat absorbing and heat delivery means whereby heat is transferred from those portions requiring cooling to those portions requiring heating, by-pass means for said heat exchange medium around each of said portions, means for cooling said fluid, means for heating said uid, means responsive to the temperature oi' the portions normally requiring cooling for causing said heat exchange medium to now through said cooling means and said heat absorbing means when cooling is required or to by-pass both of them when cooling is not required, and means responsive to the temperature o1' the portions normally requiring heating for causing said heat exchange medium to flow through said heating means and heat delivery means when heating is required and to by-pass both of them when heat is not required, and means for controlling the rate o1' ilow oi' said heat exchange fluid in accordance with its temperature for maintaining said y,temperature at a predetermined value.

12. In an air conditioning system for an enclosure having certain portions thereof normally requiring cooling and certain other portions normally requiring heating, means for absorbing heat from those portions of the enclosure normally requiring cooling, heat delivery means for those portions of the enclosure normally requiring heating, means for circulating a heatl exchange medium successively through the heat absorbing and heat delivery means whereby heat is transferred from those portions requiring cooling to those portions requiring heating, by-pass means for said heat exchange medium around each of said portions, means for cooling said uid, means for heating said uid, means responsive tothe temperature of the portions normally requiring cooling for causing said heat exchange medium to flow through said cooling means and saidheat absorbing means when cooling is required or to by-pass both of them when cooling is not required, and means responsive to the temperature oi' the portions normally requiring heating for causing said heat exchange medium to ow through said heating means and heat delivery means when heating is required and to by-pass both oi them when heat is not required, means for controlling the rate o1' flow of said heat exchange iiuid in accordance with its temperature for maintaining said temperature at a predetermined value, and means for varying said predetermined value in accordance with the load on the system.

ROBERT B. P. CRAWFORD. 

